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  1. Api's

Voices

The Voices API returns available Text-to-Speech (TTS) voices for your organization. Voice availability depends on your TTS provider configuration.

List Available Voices#

GET /voices
See List Available Voices for the complete API reference.

Voice Providers#

Local Models (Enterprise)#

Our local/on-premise TTS models provide low-latency, high-quality voice synthesis. This endpoint returns the available local voices when configured.
Available Voices:
Voice IDLanguageGenderDescription
nl_NL-pim-mediumDutch (NL)MaleNatural Dutch voice
nl_NL-ronnie-mediumDutch (NL)MaleClear Dutch voice
nl_BE-nathalie-mediumDutch (BE)FemaleBelgian Dutch voice
nl_BE-rdh-mediumDutch (BE)MaleBelgian Dutch voice
en_GB-alan-mediumEnglish (UK)MaleBritish English
en_GB-alba-mediumEnglish (UK)FemaleBritish English
en_GB-cori-mediumEnglish (UK)FemaleBritish English
en_GB-jenny_dioco-mediumEnglish (UK)FemaleBritish English
en_US-amy-mediumEnglish (US)FemaleAmerican English
en_US-joe-mediumEnglish (US)MaleAmerican English
en_US-lessac-mediumEnglish (US)FemaleAmerican English
en_US-ryan-mediumEnglish (US)MaleAmerican English
de_DE-thorsten-mediumGermanMaleGerman voice
de_DE-thorsten_emotional-mediumGermanMaleExpressive German
fr_FR-siwis-mediumFrenchFemaleFrench voice
fr_FR-tom-mediumFrenchMaleFrench voice
es_ES-davefx-mediumSpanish (ES)MaleEuropean Spanish
es_MX-ald-mediumSpanish (MX)MaleMexican Spanish
Note: Local models are only available on Enterprise plans. Contact us to request access.

ElevenLabs (BYOK)#

When using ElevenLabs with your own API key, this endpoint does NOT return ElevenLabs voices.
To use ElevenLabs voices:
1.
Check your ElevenLabs Voice Library
2.
You only have access to voices you've added to your Voice Library
3.
You only have access to custom voices you've created
4.
Copy the Voice ID from ElevenLabs
5.
Use that Voice ID in your agent's voice field
Example agent with ElevenLabs voice:
{
  "name": "Customer Support",
  "voice": "21m00Tcm4TlvDq8ikWAM", // Your ElevenLabs Voice ID
  "llm_config": {
    "provider": "openai",
    "model": "gpt-4o-realtime"
  }
}
See the BYOK documentation for setup instructions.

xAI Grok Realtime (BYOK)#

xAI Grok Realtime provides built-in ultra-low latency voices optimized for real-time conversations. These voices are not returned by the /voices endpoint because they're natively integrated into the Grok Realtime model.
Available xAI Realtime Voices:
Voice IDNameStyleBest For
araAraFemale, professionalBusiness, support
rexRexMale, friendlySales, casual
salSalNeutral, calmSupport, instructions
eveEveFemale, warmCustomer service
leoLeoMale, energeticSales, marketing
To use xAI Realtime voices:
Set the voice field in llm_config when creating or updating an agent:
{
  "name": "Sales Agent",
  "llm_config": {
    "provider": "xai_realtime",
    "model": "grok-realtime-v1",
    "voice": "ara"
  }
}
INFO
xAI Realtime combines LLM and TTS in a single model for ultra-low latency. Voice selection is part of the model configuration, not a separate TTS step.
See the BYOK documentation for xAI configuration.

Request#

Response#

Local Models Response#

{
  "voices": [
    {
      "id": "nl_NL-pim-medium",
      "name": "Pim",
      "language": "nl",
      "description": {
        "en": "Pim (Dutch, Male)",
        "nl": "Pim (Nederlands, Man)"
      }
    },
    {
      "id": "en_US-amy-medium",
      "name": "Amy",
      "language": "en",
      "description": {
        "en": "Amy (English US, Female)",
        "nl": "Amy (Engels US, Vrouw)"
      }
    }
  ]
}

ElevenLabs BYOK Response#

{
  "voices": []
}
The array is empty because ElevenLabs voices must be retrieved from your ElevenLabs account directly.

xAI Realtime Response#

{
  "voices": []
}
The array is empty because xAI Realtime voices are built into the model and configured via llm_config.voice.

Voice Selection Best Practices#

For Local Models#

1.
Match voice language to your agent's primary language
2.
Test different voices to find the best fit for your use case
3.
Consider gender and regional accent preferences

For ElevenLabs#

1.
Use consistent Voice IDs across your agents
2.
Keep a mapping of Voice IDs to names in your system
3.
Test voices in your actual use case before deploying
4.
Consider voice cloning for brand consistency

For xAI Realtime#

1.
Choose voices based on agent personality and use case
2.
Professional contexts → ara or sal
3.
Sales/marketing → rex or leo
4.
Customer service → eve or sal
5.
Test latency and voice quality in your region

Related Documentation#

Agents API - Configure agent voices
BYOK - Set up ElevenLabs or xAI
Modified at 2025-12-29 14:20:04
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